So I’m strumming an 8th pattern and it feels right to add an upstroke before the one.
As I said it feels right, adds to the song
But from a theory standpoint where does the “and” come from?
Is it from the “and” in the 4, thinking of it as the “and” from a 16th note strum?
Or just an added “and” before the one?
It does not matter musically, but I like to know the why.
Thank you
If it a + before the 1 it belongs to the 4 in 8ths.
1 + 2 + 3 + 4 + 1
As the bar will start on 1 what comes before it will be from the previous bar. 4th 8th 16th whatever, nothing can come before one, unless its in the previous bar.
Indeed, as @TheMadman_tobyjenner said
if if helps, see it like this;, with each | noting a new bar starting.
|1 + 2 + 3 + 4 +|1 + 2 + 3 + 4 +|1 + 2 + 3 + 4 +|
If you want to divde even further, you go into “Italian” territory 
|1-e-and-a-2-e-and-a-3-e-and-a-4-e-and-a-|1-e-and-a-2-e-and-a-3-e-and-a-4-e-and-a-|
The strum - takes places in the four
Previous strum in the bar - 1… 2… 3 and 4 and
I find myself adding another upstroke after last 4 and.
That’s the missing “and”
Ah ! Are you playing the 8th with all down strums ie 3 and 4 and all down picks?
And then adding a up strum after the “4 and” ?
That would make it the “a” of 4
As Lieven shows above.
I would suggest D D DUDU which will stop you adding the up strum you mention.
But if that extra strum sounds good, go for it.
That must be a case of splitting the 4th beat into 16ths with each quarter part counted as 4 then e then & then a respectively. But you only play on three of those 16ths as below.
| 4 e & a |
| D U _ U |
On the 4, your Down strum has the duration of one 16th and you immediately play an Up strum on the e. This has duration of two 16ths (equivalent to one 8th). That duration allows your strumming hand time enough to go back down again, without striking the strings, then you do another Up strum on the a.
Here is an example. Two bars each of Stuck 3&4 G then C chords.
……or you could be playing beat 4 as a triplet, counting it as “4 and a” with the “and” being slightly earlier than in 1/8 or 1/16 strumming.
Splitting the last beat into a triplet would give directional strumming of Down Up Down. @Thallman describes his motion as Down Up Up.
Yeah, true.
What everyone has said could be true but with out hearing what you’re doing with a metronome or backing track it’s hard to say.
You could just be adding an extra note that shouldn’t be there and not playing in time which is a big problem if its become a habit. Timing is the backbone of music and without it you’ll never beable to play with others.
